Rhyolite- felsic, fast cooling rate, extrusive, fine grained--grayish white with a little yellow. may have brown-red stripes Scorria- mafic, fast cooling rate, extrusive, fine grained-- red and very light (weight) has bubbles Granite- felsic, slow cooling rate, intrusive, coarse grained -- pink and white over all with black spots Andesite- mafic, fast cooling rate, extrusive, fine grained -- gray-- may have little black specs Diorite- felsic, slow cooling rate, intrusive, coarse grained -- half felsic and mafic appearance (like oreo ice cream) still fesic Basalt- mafic, fast cooling rate, extrusive, fine grained- (yellow/ brown/ black mix) Pumice- felsic, fast cooling rate, extrusive, fine grained-- gray and very light (weight) Gabbro- mafic, half slow, half fast cooling rate, both intrusive and extrusive, porphyritic Obsidian- felsic, fast cooling rate, extrusive, glassy texture (no crystals) -- Completely black but felsic
Sedimentary Rocks
Conglomerate- clastic, poorly sorted, contains fragments, round fragments - blob of pebbles Coal- organic, Black, contains plant material.- black Limestone- chemical, contains Geodes, bubbles when acid is applied, common in our area-redish brown Brecchia- clastic. poorly sorted,contain angular fragments- looks like cement Shale- clastic,well sorted, fossils and stratification-blackish gray Chert-clastic well sorted, stratification, scratches limestone-whitish yellow Sandstone- clastic, well sorted, stratification, looks like sand Coquina- organic, angular fragments, bubbles when acid is applied- sea shells Siltstone-clastic, well sorted, stratification, bubbles when acit it applied- very red
Metamorphic Rocks
Quartzite-non- foliated, originally quartz, formed by heat Marble- non-foliated, originally limestone, formed by heat, sparkles- white Schist- foliated- originally chlorinite, formed by pressure, breaks into layers Gneiss- foliated, muscovite, formed by pressure and heat, banded Slate- foliated, originally shale, formed by pressure,breaks into layers
Rhyolite- felsic, fast cooling rate, extrusive, fine grained--grayish white with a little yellow. may have brown-red stripes
Scorria- mafic, fast cooling rate, extrusive, fine grained-- red and very light (weight) has bubbles
Granite- felsic, slow cooling rate, intrusive, coarse grained -- pink and white over all with black spots
Andesite - mafic, fast cooling rate, extrusive, fine grained -- gray-- may have little black specs
Diorite- felsic, slow cooling rate, intrusive, coarse grained -- half felsic and mafic appearance (like oreo ice cream) still fesic
Basalt- mafic, fast cooling rate, extrusive, fine grained- (yellow/ brown/ black mix)
Pumice- felsic, fast cooling rate, extrusive, fine grained-- gray and very light (weight)
Gabbro- mafic, half slow, half fast cooling rate, both intrusive and extrusive, porphyritic
Obsidian- felsic, fast cooling rate, extrusive, glassy texture (no crystals) -- Completely black but felsic
Sedimentary Rocks
Conglomerate- clastic, poorly sorted, contains fragments, round fragments - blob of pebbles
Coal- organic, Black, contains plant material.- black
Limestone- chemical, contains Geodes, bubbles when acid is applied, common in our area-redish brown
Brecchia- clastic. poorly sorted,contain angular fragments- looks like cement
Shale- clastic,well sorted, fossils and stratification-blackish gray
Chert-clastic well sorted, stratification, scratches limestone-whitish yellow
Sandstone- clastic, well sorted, stratification, looks like sand
Coquina- organic, angular fragments, bubbles when acid is applied- sea shells
Siltstone-clastic, well sorted, stratification, bubbles when acit it applied- very red
Metamorphic Rocks
Quartzite-non- foliated, originally quartz, formed by heat
Marble - non-foliated, originally limestone, formed by heat, sparkles- white
Schist- foliated- originally chlorinite, formed by pressure, breaks into layers
Gneiss- foliated, muscovite, formed by pressure and heat, banded
Slate- foliated, originally shale, formed by pressure,breaks into layers